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The objective of this study was to determine the effects that parity may have on production, reproduction and the metabolic status of Holstein cows managed in a production system based on total mixed ration and pasture. Primiparous (n = 22) and multiparous (n = 24) cows from a dairy farm research station in Uruguay were used in a completely randomized design. Body weight (BW), body condition score (BCS) and backfat thickness (BFT) were recorded weekly from -30 to 70 days postpartum. Milk production was measured daily, and milk composition was determined weekly. Resumption of postpartum ovarian activity and progesterone profiles were measured three times a week based on milk progesterone. Blood was collected to determine the levels of glucose, insulin-like growth factor I (IGF-1), insulin, non-esterified fatty acids (NEFA), β-hydroxybutyrate (BHB), albumin, total protein and cholesterol. Milk production and components were lower for primiparous cows (p < 0.01) than multiparous cows. Body weights were also lower in primiparous cows than in multiparous cows (p < 0.05); however, BCS and BFT were greater (p < 0.01) in primiparous cows than in multiparous cows. Primiparous cows had greater levels of glucose, insulin and IGF-1 and lower concentrations of NEFA and BHB (p < 0.01) than multiparous cows. The intervals from calving to first ovulation were not affected by parity; however, primiparous cows showed less abnormal cycles (27.2%) than multiparous cows (50.0%) (p < 0.01). The present study found that a feeding system based on TMR and pasture was sufficient to produce over 25 L of milk per day without extending their calving to first ovulation interval in primiparous and multiparous cows. However, multiparous cows showed a greater imbalance in metabolic and hormonal profiles than primiparous cows, causing abnormal ovarian activity., (Copyright © 2018 Elsevier B.V. All rights reserved.)